First of all, it depends on whether you are talking raw or equipped. A 500 equipped bench doesn't sound very impressive, except for small or female lifters. I can't bench 400 raw but I can bench 425x2 with a slingshot, within a few months of training for equipped bench it wouldn't be unrealistic to expect that I could bench 500.

For raw lifters, there are not many under SHW that can bench 500. That would be an elite level raw bench in any other weight class. Steroids also make a much bigger difference for bench than for squat or deadlift, apparently due to there being a high concentration of androgen receptors in the shoulder area. 500+ benches are much more common in untested meets.

Looking at IPF men's open raw records, Dennis Cornelius has the 120kg record with 253kg/557lbs. Garrett Blevins has the 105 record with 224, which is only about 493, but apparently there was a guy at CPU nationals who benched 230kg (506) the other day. Dennis Cieri has benched 233kg at 93, and 232.5 in a full meet. So unless you are over 120kg or your name is Dennis, a 500lbs bench is pretty rare. Dennis Cieri is basically a freak, just like Jeremy Hoornstra who has benched 663 at 242 and over 700 in the gym.

The answer is : really fucking rare. less than 1/10,000 people, probably. When I say this, I'm assuming a bench press that would be passable in a powerlifting meet. No bro-spots, no heaving/bouncing off the chest.

I'll give you a reference point to work with. You can find folks who don't work out but can still bench 300. It's uncommon, but it happens. You will never, ever find a non-lifter who is capable of a 500 bench. The number of living humans who are under 200 lbs and can do it is almost certainly less than 20. You'll likely never see a 500 lbs bench presser in a commercial gym. It's an extremely rare thing. I have never seen a 500 lbs bench press in a commercial gym. Even in a hardcore gym, like the Metroflex gym I go to, you will likely only have a few members who can do it. At my gym, I'm fairly certain the number is less than 5.

So in summary and to answer your question directly, just being a 'big guy' does not mean a person is likely to have accomplished this feat. I'm not saying the person you're talking about is lying, by any means, but it is a distinct possibility.

We've got one guy at my gym who might have been able to do that. If he wasn't there, he was close. I know his shirted bench was around 750 in competition as a SHW. He's probably the strongest person ever to live in Maine.

Any way you cut it, a 500 pound bench is extremely rare. I'd go much rarer than Flip's estimate of 1 in 10,000, which would work out to about 375,000 men on the planet who could perform this feat.

I'm just guessing, but I'd be surprised if there are 10,000 men alive who can do this feat. That would work out to about one in 375,000 men.

Steroids also make a much bigger difference for bench than for squat or deadlift, apparently due to there being a high concentration of androgen receptors in the shoulder area.

what nonsense. This isn't close to being true.

I can't personally verify it, but according to Greg Nuckols it is true. Perhaps you know more than him?

From his article "Do women need to train differently than men?"

"The muscles of the shoulder girdle have more androgen receptors than any other muscle group. This means that testosterone’s anabolic effects are most potent on these muscles. "

I suppose I was incorrect is saying shoulders rather than shoulder girdle. Anyway, that partly explains why no all-time bench records are held by lifters that compete in tested feds (if they aren't natural they at least aren't going all out) while the IPF has Ray Williams with the all time squat record plus Jezza Uepa and Kelly Branton not far behind.

As most have said here it is very rare, but it may well be the case this guy is one of the few who can! I've recently gotten to know someone at my gym who would talk a lot about how much he and his brother used to lift back in the day and i must admit i didn't really believe everything he said and thought he was probably exaggerating... anyway i got to know him pretty well and it turned out everything he claimed is true and more! He's Neil Confessore and his brother Chris was the best bencher in the world at his peak with multiple WRs.

He gave me an original copy of one of Chris's bench programs which is real old school, just talks about how to get big and how to get strong none of the usual crap a lot of people like to spout these days.

Neil benches that sort of weight now (he's coming up to 60). When he was younger competing in the uspf he benched over 500, I read an article on him in power magazine from the 90s doubt you'll find much on the internet from back then.

I lifted in a gym back in 1990 that probably had a “kid” who could BP 500 pounds. If you looked at him he kind of looked like a big fat kid. Then he’d put 135 on the bar and rep it a bunch of times. Then 225 for 10. Then 315 for 10. Then he’d start his 3x10 with 405. He never struggled with any rep. I asked him how much he could push and he said he didn’t know. He’d never tried maxing. I tried to get him to find out, but he wasn’t comfortable trying more weight. I was 19 at the time and he was probably 18 since he graduated high school a year after I did. He’s a good example of why I say you never know how strong someone is by looking at them.

He gave me an original copy of one of Chris's bench programs which is real old school, just talks about how to get big and how to get strong none of the usual crap a lot of people like to spout these days.

while the IPF has Ray Williams with the all time squat record plus Jezza Uepa and Kelly Branton not far behind.

It's problematic to assume any of them are actually natural.

Squat records in general have been going up faster and more regularly than bench, period. That has nothing to do with steroids.

I can tell you that for me, steroids have had a far bigger impact on leg development than shoulders. But honestly man, all you have to do is look at an IFBB pro bodybuilder to see how obvious it is that your statement is silly.

I will add that the statement "The muscles of the shoulder girdle have more androgen receptors than any other muscle group." seems to be verifiable. But this does not translate to a massive difference in the ability to improve bench versus squat. If you had said 'steroids make a slightly more discernible difference with bench as compared to squat', you might be able to support your argument (although I doubt this too). 'makes a much bigger difference' is just empirically false.